This invention relates to a novel improvement of positioning apparatus for transferring pallets in a linear station machine or the like. Generally, a transfer machine such as a linear station machine or the like is used to perform necessary working operations by the various working units arranged along both sides thereof. And the transfer of works or workpieces is commonly performed by the pallets carrying jig plates thereon.
The conventionally linear station machine of pallets-transfer type has a pallet transfer track such as a dovetailed groove continued for defining a transfer direction on the bed thereof, and also every pallet has a sliding surface for sliding along that of said transfer track.
These sliding surfaces are simultaneously used as base surfaces for the positioning of pallets so that the sliding surfaces must be finished with high accuracy and it is a danger that chips will lodge between these sliding surfaces and cause wear or decrease the finishing accuracies of the works. Furthermore, it requires a lubricating system comprised of a highly complicated mechanism to decrease abrasions and sticking of said sliding surfaces.